Converters, such as those which convert input AC power into output DC power for supply to one or more loads, have many applications. For example, converters are used to convert three or more phase input AC power into output DC power for onboard DC loads of an aircraft. While the aircraft is on the ground, the input AC power is typically supplied by a ground power cart; on the other hand, while the aircraft is in the air, the input AC power is supplied by generators driven by the engines of the aircraft. Thus, the converter converts the input AC power into DC power for onboard DC loads while the aircraft is on the ground or in the air.
A typical AC to DC converter includes multiple rectifiers connected together in a bridge configuration. The rectifiers are controlled so as to convert the input AC power into output DC power. A rectifier bridge, however, typically presents a non-unity power factor to the input AC source. Hence, the input AC source must have a greater capacity than if the rectifier bridge were to present a unity power factor load to the input AC source. Moreover, the output DC of a rectifier bridge typically exhibits a substantial amount of harmonic ripple.
The present invention is directed to an arrangement which controls the rectifiers of a rectifier bridge so that the rectifier bridge presents a unity power factor load to the input AC source and so that the harmonic ripple in the output DC of the rectifier bridge is suppressed, minimized, reduced, and/or eliminated.